On their second album, the xx face the challenge offered to all bands who emerge fully-formed, with a distinct and instantly recognisable musical aesthetic: what to do next? The London trio's answer is to take their already skeletal frame and further strip away any excess fat: for the most part Coexist's songs are defined as much by space as by sound. The gaps bring greater emphasis to the spidery guitar lines, the occasional steel pan, the distant icicles of piano, and the voices of Romy Madley-Croft and Oliver Sim. The album's theme is heartbreak and the intensity with which love catapults one into a private world: a tone set in the tender single, Angels, where Madley-Croft sings "they would be as in love with you as I am", with the private knowledge that only intimacy brings. That's a solo voice number, but Madley-Croft and Sim echo each other across the album, never quite duetting, more like two people singing their own versions of the same story, to captivating effect, both aching with regret. A low-key triumph.